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I clicked on this because I worked on the infra that simulated the famous blackhole sim in interstella. I thought "oooh this is interesting I wonder how they a

I clicked on this because I worked on the infra that simulated the famous blackhole sim in interstella. I thought "oooh this is interesting I wonder how they are going to do physically accurate on an end device" Recalling how the original particle sim was something like 100TB, took 2 weeks to generate and seemed to write in a way that killed disks. but that was >10 years ago, so what clever stuff has been done to model it locally. Its been a long time since I've looked at black holes, but what I'm not understanding is why the stars surrounding the black hole are just points, and more over why the lines are straight to the centre of the hole. from memory the way light enters the hole appears non-linear and changes on view point.

vee-kay 2mo ago
Someone refers to a sci-fi-esque (more imaginative than scientifically accurate) virtual rendition of an interesting scientific phenomenon (black hole) in a fanous sci-fi movie (Interstellar), in their scientific analysis/critique comment on a HN thread about the virtual sci-fi-esque rentition of such a sci-fi object (black hole)(yes, a simplified easy-on-eyes pseudo-accurate rendition of a black hole, for VR/AR immersion at home, counts as sci-fi-esque, IMHO), and someone else who worked on such famous object (black hole) depicted in that exact sci-fi movie, responds to the comment. Peak HN, right here!
- reactordev 2mo ago
  You have reached the end of the internet. We hope you enjoyed your stay. /s
aplavin 2mo ago
> why the stars surrounding the black hole are just points, and more over why the lines are straight to the centre of the hole Sorry for confusion! Points + lines are just other users looking at the black hole right now, their camera locations and lines of sight. Nothing more! In the first hours of HN frontpage, there were a lot – and I can see how one can understand them as parts of actual scene :) I decided not to change their style, not to make them more subtle – half a day later, there are already way fewer users online, and these points/lines don't look as crowded as they did.
- KaiserPro 2mo ago
  Aha! understood Yeah I couldnt work out what they were in relation too
aplavin 2mo ago
> I thought "oooh this is interesting I wonder how they are going to do physically accurate on an end device" Recalling how the original particle sim was something like 100TB, took 2 weeks to generate and seemed to write in a way that killed disks. but that was >10 years ago, so what clever stuff has been done to model it locally. Yes, totally reasonable question! Those terabytes surely were things like fluid/matter motion around the black hole, stuff like this. Here, I definitely don't simulate matter motion around the black hole as a particle/fluid sim does – instead, I focus on simulating the effects of the black hole itself. Matter distribution and motion (where it is used at all, ie not in camera mode) is described by simple functions phenomenologically. The single most notable effect of a black hole is strong light bending (+ time delays), and it is properly simulated in all modes in this app. Next, relativistic beaming (Doppler boosting) and gravitational redshift are simulated for the accretion disk emission as well. If you zoom out, the jet is visible as well – it's relatively far away, so it is rendered with special relativity only; ie, no GR, but full volumetric rendering taking all SR effects into account. Admittedly, the GR-SR seam implementation can be improved somewhat.

vee-kay 2mo ago

Someone refers to a sci-fi-esque (more imaginative than scientifically accurate) virtual rendition of an interesting scientific phenomenon (black hole) in a fanous sci-fi movie (Interstellar), in their scientific analysis/critique comment on a HN thread about the virtual sci-fi-esque rentition of such a sci-fi object (black hole)(yes, a simplified easy-on-eyes pseudo-accurate rendition of a black hole, for VR/AR immersion at home, counts as sci-fi-esque, IMHO), and someone else who worked on such famous object (black hole) depicted in that exact sci-fi movie, responds to the comment. Peak HN, right here!

reactordev 2mo ago
You have reached the end of the internet. We hope you enjoyed your stay. /s

aplavin 2mo ago

> why the stars surrounding the black hole are just points, and more over why the lines are straight to the centre of the hole Sorry for confusion! Points + lines are just other users looking at the black hole right now, their camera locations and lines of sight. Nothing more! In the first hours of HN frontpage, there were a lot – and I can see how one can understand them as parts of actual scene :) I decided not to change their style, not to make them more subtle – half a day later, there are already way fewer users online, and these points/lines don't look as crowded as they did.

KaiserPro 2mo ago
Aha! understood Yeah I couldnt work out what they were in relation too

aplavin 2mo ago

> I thought "oooh this is interesting I wonder how they are going to do physically accurate on an end device" Recalling how the original particle sim was something like 100TB, took 2 weeks to generate and seemed to write in a way that killed disks. but that was >10 years ago, so what clever stuff has been done to model it locally. Yes, totally reasonable question! Those terabytes surely were things like fluid/matter motion around the black hole, stuff like this. Here, I definitely don't simulate matter motion around the black hole as a particle/fluid sim does – instead, I focus on simulating the effects of the black hole itself. Matter distribution and motion (where it is used at all, ie not in camera mode) is described by simple functions phenomenologically. The single most notable effect of a black hole is strong light bending (+ time delays), and it is properly simulated in all modes in this app. Next, relativistic beaming (Doppler boosting) and gravitational redshift are simulated for the accretion disk emission as well. If you zoom out, the jet is visible as well – it's relatively far away, so it is rendered with special relativity only; ie, no GR, but full volumetric rendering taking all SR effects into account. Admittedly, the GR-SR seam implementation can be improved somewhat.